Some species are big in greenhouses for his or her unusual foliage and typically showy flowers. Low-growing species are in style in rock gardens and rock walls and as the border in garden borders.Sedum plant size depends upon its type and condition. That grows 1 to 3 feet in height. Slow growing types can keep nice and little during a pot, whereas quick, ground cowl varieties like herbaceous plants will unfold up to 1″ a month within the season.